Anti-ESR1 (phospho S167) Antibody

Phosphorylation of estrogen receptor alpha at serine 167 is a key regulatory event linked to ligand-independent activation through the MAPK/ERK signaling cascade, and detecting this specific post-translational modification is central to studies of breast cancer progression, endocrine resistance, and nuclear receptor signaling.

This rabbit polyclonal IgG antibody from Antibodies.com is raised against the ESR1 phospho S167 epitope and is validated for Western Blot detection of the phosphorylated receptor in human samples. Supplied as 100 µl of unconjugated antiserum in a vial, the reagent fits into immunoblotting workflows that probe ERα activation status in cell lysates, tissue homogenates, and tumor-derived material.

Researchers studying hormone-responsive cancers, tamoxifen resistance mechanisms, and kinase crosstalk with nuclear receptors rely on phospho-specific ESR1 detection to distinguish activated receptor pools from total ERα levels. The polyclonal format offers broader epitope coverage around the phospho-S167 site, which can be useful when working with samples where this modification is sub-stoichiometric or where surrounding sequence variation is a concern.

For storage, the antibody should be refrigerated and protected from light, with aliquoting recommended to limit freeze-thaw cycles and preserve antigen-binding activity over the working shelf life of the reagent.